iPhone X Bottom Mic Not Working When On Speakerphone

When i use my phone to make calls, on normal in call mode the other person can hear me fine.

BUT.. when i put it on speakerphone the other person can't hear me! I literally have to shout so they can hear, its very muffled/quiet.

it's also the same when i try to use voice memo's.

i dont have any case on the phone so nothings blocking it what so ever

any idea's??